Towing capacity

Firstly, I apologise as I know this topic has been done to death. I used the search and read through a lot of previous posts but still can’t get my head around it. Was looking in particular for a diagram that I had seen put up before but couldn’t seem to find it.

i have a 2015 Toyota prado Gxl auto.

Just weighed with me in it at 2.58t (arb roobar, suspension, racks etc). From what I can see max towing weight is suggested at 2.5t, tow ball down weight max 250kg.

i need to work out the max I can tow a the boat I am looking to get will be pushing the limit. It should come under 2.5t, but I want to make sure will still b ol with the mods I have put on the car.

assuming fully loaded car would be, say, 2.75 for example, how can I work out the max I will be able to safely tow?

thanks guys. Maths never was my strong point! 

Feral's picture

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Date Joined: 01/11/06

 You can only tow 2.5t.. Its

Wed, 2019-10-09 12:05

 You can only tow 2.5t.. Its got nothing to do with your vehicle weight (the heavier the car the better actually) you will need to find out you max combined vehicle weight to make sure it is over the gross vehicle weight(2.75t) and boat (2.5t).. The tow ball down weight means nothing to your towing weight as the boat must be weighted alone with jocky wheel down and not connected to the tow vehicle.

Not sure if I explained that well enough but I'm sure you'll figure it out 

The Saint's picture

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Date Joined: 30/01/13

Have a look

Wed, 2019-10-09 12:29

Have a look at:

Go to "About GVM Check" (next to Home), then go to "Car and Van weights explained".

A handy diagram that might help you work thing out.


Feral's picture

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Date Joined: 01/11/06

 Had a bit of a look

Wed, 2019-10-09 12:34

 Had a bit of a look online

  • Gross Vehicle Mass
    2990 kg
  • Gross Combination Mass
    5370 kg
  • Payload
    660 kg
  • Towing Capacity (braked)
    2500 kg
  • So if you can have your vehicle weight at 2870kg and boat at 2500kg and be legal.. If the boat is lighter you can add a little to the car up to 2990kg  (as long as boat was under 2370kg

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Date Joined: 26/03/17

awesoem!thanks heaps

Wed, 2019-10-09 13:14


thanks heaps guys.

that clears a few things up.. hopefully all fits as really like the boat!.......almost justiofying to myself trading in the car if it doesnt lol!

Posts: 497

Date Joined: 26/03/17

okie dokie....i think i have

Wed, 2019-10-09 15:15

okie dokie....

i think i have this...


gvm is 2990

towing capacity is 2500

so gcm should be 5490?


whcih means.....

if car is at 2.75t loaded up



doesnt that mean could tow up to 2740kg?

then i guess the ball weight come sin,, so assuming 250kg, then that would give me max of 2490?

does this sound like ive worked it out right?

Posts: 497

Date Joined: 26/03/17

but i gues wouldnt kow the

Wed, 2019-10-09 15:18

but i gues wouldnt kow the actual tow ball downweight without knowing the aggregate trailer mass........

Posts: 444

Date Joined: 23/04/14

Not quite righ.

Wed, 2019-10-09 22:46

Firstly, the ratings given are maximums, not suggestions.  You can’t legally exceed them.

GCM is given by the manufacturer, it’s not GVM plus Tow Rating (although it can be if that’s what the manufacturer states). 

If your boat is 2500kg then your allowed GVM is 5370 (GCM) - 2500 (Tow weight) = 2870.

Based on Feral’s numbers, Tare weight = GVM - Payload = 2990 - 660 = 2330kg.

With your actual GVM at 2870 your payload is now reduced from 660kg to 540kg (GVM - tare weight).

Ball weight is counted as part of payload, so if you assume a ball weight of 250kg (10% of tow weight), your payload is now 540 - 250 = 290kg.

Therefore, if towing your maximum allowable load of 2500kg, you can only have 290kg of payload.  That includes fuel, passengers, gear plus any accessories.  Let’s assume a fuel tank of fuel (120kg) plus you as driver (80kg), that’s 200kg of payload.  Now the most you can add is 90kg.  Bear in mind that’s 90kg above bare showroom condition.  

Let’s further assume you’ve put on a bull bar and second battery, which together would be lucky to be less than 90kg.  So you’ve hitched your boat up, filled up your tanks for trip, and jumped in the driver seat.  You can now not legally add any more weight to the vehicle.





Darren253's picture

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Date Joined: 23/07/16

5370kg (GCM) - 2500kg (Boat)

Thu, 2019-10-10 08:42

5370kg (GCM) - 2500kg (Boat) - 2580kg (Actual weighbridge weight with driver) = payload of 290kg additional to the driver

If you add the downforce on the ball weight for the payload calculation, you would need to remove it from the trailer axle weight for GCM calculation. 5370kg (GCM) - 2300kg (Boat Axles) - 2580kg (Actual weighbridge weight with driver) - 200kg Tow ball = payload of 290kg.

All in all its around the same numbers, but what you cant do is legally load up your boat/car with 500kg worth of camping gear and beer and expect to be tickety boo in an accident... I would guestimate that 75% of people heading north for the winter be it with caravans or boats would be illegal if they really looked into it.

Posts: 444

Date Joined: 23/04/14

My mistake

Sat, 2019-10-12 14:12

 I counted ball weight twice.

Still, fill the tanks, another person and you’re still nearly at the limit.





Posts: 497

Date Joined: 26/03/17

cheers guys!.... that makes

Thu, 2019-10-10 10:02

cheers guys!.... that makes sense.

i had thought that the gcm was 5490, so think that was where i was getting confused.

looks like i may have to opt for a lighter trailer!..... or a bigger engine :p

Posts: 771

Date Joined: 09/10/06

 Not many cars can tow there

Thu, 2019-10-10 10:38

 Not many cars can tow there max tow weights with any payload.  Out of all the commercial 3.5t towing utes, only one can get close to 3t tow weight and keep there payload. I think the hilux was only 2.7t. Plenty of articialls out there


backlash's picture

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Date Joined: 12/10/10


Fri, 2019-10-11 10:09

 let's see if this works


Posts: 497

Date Joined: 26/03/17

Pretty sure that is the

Fri, 2019-10-11 16:58

Pretty sure that is the diagram i was looking for ! cheers!

Stevo81's picture

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Date Joined: 16/04/12

Fri, 2019-10-11 18:53


                                   ••••••••  Electrical Contractor NOR  ••••••••

ranmar850's picture

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Date Joined: 12/08/12

The link posted above by Stevo81

Sat, 2019-10-12 18:04 as good an explanation as you will get.